Anti-mikrobiālās plānās kārtiņas: izgatavošanas tehnoloģija un īpašību noteikšana.
Date
2022
Authors
Vibornijs, Viktors
Journal Title
Journal ISSN
Volume Title
Publisher
Latvijas Universitāte
Abstract
Šī pētījuma galvenais mērķis ir izstrādāt plānās kārtiņas pārklājumu ar anti-mikrobiālām īpašībām. Šim mērķim tika pētīts volframa oksīda un vara kombinētas plānās kārtiņas pārklājums uz PET substrāta, kura struktūras parametru pamatā ir caurspīdīgs ap 120 nm biezs volframa oksīda slānis ar tam virsū uzklātu 20 nm vara slāni, kas, savukārt, ir apsegts ar 120 nm volframa oksīda slāni – WOx/Cu/WOx. Anti-mikrobiālo efektu noteikšanai tika adaptētas testēšanas metodoloģijas JIS Z 2801 “Antimicrobial products-Test for antimicrobial activity and efficacy” (Association JS 2001) un ES ISO 22196 “Measurment of antibacterial activity on plastic surfaces” (ES ISO 22196). Testēšana tika veikta ar E.coli, S.aureus baktērijām un MS2 bakteriofāgu. Izmantojot optimizēto testēšanas metodoloģiju, tika novērtētas paraugu anti-mikrobiālās īpašības un pētīta paraugu anti-mikrobiālā efektivitāte. Salīdzinot iegūtos datus ar paraugu fizikālo parametru raksturošanas datiem, tika iegūts stabilais WOx/Cu/WOx G498 paraugs, kura anti-bakteriālā iedarbība >4 log samazināšanas pakāpi. Efektivitāte tika pierādīta gan baktēriju kultūrās pēc kontakta ar pārklājumu, audzējot šķidrajā barotnē, gan ar koloniju veidojošo vienību noteikšanas uzsējama metodi. Testējot paraugus ar MS2 bakteriofāgu, vairākiem WOx/Cu/WOx paraugiem konstatēta spēja samazināt virālo daļiņu skaitu līdz 6 log samazināšanas pakāpei. Šūnu dzīvotspējas testa rezultātā novērojama E.coli un S.aureus metaboliskās aktivitātes samazināšanās pēc baktēriju inkubēšanas uz testējamām virsmām. Salīdzinot rezultātus ar antimikrobiālās aktivitātes testiem, tika konstatēts, ka šūnu dzīvotspējas samazinājums pēc kontakta ar WOx/Cu/WOx, nenorāda uz baktēriju šūnu ilglaicīgo inaktivāciju vai pilno iznīcināšanu. Reaktīva skābekļa savienojumu daudzums baktēriju suspensijā, pēc inkubēšanas uz testējamām virsmām, nekorelēja ar testēto pārklājumu anti-mikrobiālo efektivitāti. Pārklājuma un barotnes kontakta gadījumā tiek novērota reaktīva skābekļa savienojumu (ROS) veidošanās arī paraugiem, kuri vāji (<1 logaritmiskās pakāpes) inhibē baktērijas. Pētījumi tika veikti LU Cietvielu fizikas institūtā, Plāno kārtiņu laboratorijā un Latvijas Biomedicīnas pētījumu un studiju centrā.
The main objective of this research is to develop a thin film coating with anti-microbial properties. For this purpose, a combined tungsten oxide and copper thin film coating on a PET substrate was tested, the structural parameters of which are based on a transparent tungsten oxide layer about 120 nm thick with a 20 nm copper layer applied on top of it, which in turn is covered with a 120 nm tungsten oxide layer – WOx/Cu/WOx. The testing methodologies JIS Z 2801 "Antimicrobial products-Test for antimicrobial activity and efficacy" (Association JS 2001) and ES ISO 22196 "Measurement of antibacterial activity on plastic surfaces" (ES ISO 22196) were adapted to determine the antimicrobial effects. Testing was performed with E.coli, S.aureus bacteria and MS2 bacteriophage. Using the optimized testing methodology anti-microbial properties of the samples were evaluated and the anti-microbial efficiency of the samples was studied. By comparing the obtained data with the characterization data of the physical parameters of the samples, a stable WOx/Cu/WOx G498 sample was obtained, which has an anti-bacterial effect >4 Log reduction rate. Efficacy was observed for both bacteria cultures after contact with the coating, regrowing bacteria in liquid media, and by the inoculation method of colony-forming units. When testing coatings efficiency with MS2 bacteriophage 6 log reduction rate were detected after contact with several WOx/Cu/WOx samples. In case of the cell viability testing, a decrease in the metabolic activity of E.coli and S.aureus can be observed after incubation of the bacteria on the test surfaces. Comparing the results with anti-microbial activity tests, it was found that the decrease in cell viability after contact with WOx/Cu/WOx does not indicate long-term inactivation or complete destruction of bacterial cells. The amount of reactive oxygen compounds in the bacterial suspension, after incubation on the test surfaces does not correlate with the anti-microbial efficiency of the coatings. After the contact between the coating and the culture medium, the formation of reactive oxygen species (ROS) is observed for samples which weakly (<1 log reduction) inhibits bacteria. The researches were carried out at the Institute of Solid State Physics, Thin Film Laboratory and Latvian Biomedical Research and Study Center.
The main objective of this research is to develop a thin film coating with anti-microbial properties. For this purpose, a combined tungsten oxide and copper thin film coating on a PET substrate was tested, the structural parameters of which are based on a transparent tungsten oxide layer about 120 nm thick with a 20 nm copper layer applied on top of it, which in turn is covered with a 120 nm tungsten oxide layer – WOx/Cu/WOx. The testing methodologies JIS Z 2801 "Antimicrobial products-Test for antimicrobial activity and efficacy" (Association JS 2001) and ES ISO 22196 "Measurement of antibacterial activity on plastic surfaces" (ES ISO 22196) were adapted to determine the antimicrobial effects. Testing was performed with E.coli, S.aureus bacteria and MS2 bacteriophage. Using the optimized testing methodology anti-microbial properties of the samples were evaluated and the anti-microbial efficiency of the samples was studied. By comparing the obtained data with the characterization data of the physical parameters of the samples, a stable WOx/Cu/WOx G498 sample was obtained, which has an anti-bacterial effect >4 Log reduction rate. Efficacy was observed for both bacteria cultures after contact with the coating, regrowing bacteria in liquid media, and by the inoculation method of colony-forming units. When testing coatings efficiency with MS2 bacteriophage 6 log reduction rate were detected after contact with several WOx/Cu/WOx samples. In case of the cell viability testing, a decrease in the metabolic activity of E.coli and S.aureus can be observed after incubation of the bacteria on the test surfaces. Comparing the results with anti-microbial activity tests, it was found that the decrease in cell viability after contact with WOx/Cu/WOx does not indicate long-term inactivation or complete destruction of bacterial cells. The amount of reactive oxygen compounds in the bacterial suspension, after incubation on the test surfaces does not correlate with the anti-microbial efficiency of the coatings. After the contact between the coating and the culture medium, the formation of reactive oxygen species (ROS) is observed for samples which weakly (<1 log reduction) inhibits bacteria. The researches were carried out at the Institute of Solid State Physics, Thin Film Laboratory and Latvian Biomedical Research and Study Center.
Description
Keywords
Bioloģija , Anti-mikrobiālie pārklājumi , Magnetronā izputināšana , Testēšanas metodoloģija , MS2 bakteriofāgs , Volframa plānās kārtiņas